grakn (empty) → 0.2.0
raw patch · 12 files changed
+864/−0 lines, 12 filesdep +MissingHdep +QuickCheckdep +aesonsetup-changed
Dependencies added: MissingH, QuickCheck, aeson, base, containers, grakn, hspec, http-client, http-media, markdown-unlit, mtl, process, regex-posix, scientific, servant, servant-client, text
Files
- LICENSE +202/−0
- Setup.hs +3/−0
- features/Main.hs +18/−0
- grakn.cabal +102/−0
- src/Grakn.hs +48/−0
- src/Grakn/Client.hs +115/−0
- src/Grakn/Pattern.hs +58/−0
- src/Grakn/Property.hs +145/−0
- src/Grakn/Query.hs +52/−0
- src/Grakn/Util.hs +27/−0
- test/Example.lhs +93/−0
- test/Main.hs +1/−0
+ LICENSE view
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+ Setup.hs view
@@ -0,0 +1,3 @@+import Distribution.Simple++main = defaultMain
+ features/Main.hs view
@@ -0,0 +1,18 @@+module Main where++import Env+import qualified Spec+import System.Exit (exitFailure, exitSuccess)+import Test.Hspec.Runner (Summary (Summary), hspecResult)++main :: IO ()+main = do+ started <- envStart+ if started+ then do+ Summary _ numFailures <- hspecResult Spec.spec+ envStop+ if numFailures /= 0+ then exitFailure+ else exitSuccess+ else exitFailure
+ grakn.cabal view
@@ -0,0 +1,102 @@+name: grakn+version: 0.2.0+synopsis: A Haskell client for <http://grakn.ai Grakn>+description: A Haskell client for <http://grakn.ai Grakn>+license: Apache-2.0+license-file: LICENSE+homepage: https://github.com/graknlabs/grakn-haskell+author: Grakn Labs+maintainer: community@grakn.ai+category: Database,Graphs+build-type: Simple+extra-source-files: test/Example.lhs+cabal-version: >=1.10++source-repository head+ type: git+ location: http://github.com/graknlabs/grakn-haskell++library+ build-depends: base >= 4.7 && < 5+ , containers == 0.5.*+ , process == 1.4.*+ , aeson == 1.*+ , scientific == 0.3.*+ , text == 1.2.*+ , regex-posix == 0.95.*+ , servant == 0.9.*+ , servant-client+ , http-client+ , mtl+ , http-media+ hs-source-dirs: src+ exposed-modules: Grakn+ other-modules: Grakn.Util+ , Grakn.Query+ , Grakn.Pattern+ , Grakn.Property+ , Grakn.Client+ default-language: Haskell2010++ default-extensions: MultiParamTypeClasses+ , FlexibleInstances+ , FlexibleContexts+ , DataKinds+ , TypeOperators++test-suite test+ type: exitcode-stdio-1.0+ main-is: Main.hs+ hs-source-dirs: test,src+ build-depends: base >= 4.7 && < 5+ , grakn+ , containers == 0.5.*+ , process == 1.4.*+ , aeson == 1.0.*+ , scientific == 0.3.*+ , text == 1.2.*+ , regex-posix == 0.95.*+ , servant == 0.9.*+ , servant-client+ , http-client+ , mtl+ , http-media+ , hspec+ , QuickCheck >= 2.8+ , markdown-unlit+ , MissingH+ other-modules: Example+ default-language: Haskell2010+ ghc-options: -pgmL markdown-unlit+ default-extensions: MultiParamTypeClasses+ , FlexibleInstances+ , FlexibleContexts+ , DataKinds+ , TypeOperators++test-suite accept+ type: exitcode-stdio-1.0+ main-is: Main.hs+ hs-source-dirs: features,src+ build-depends: base >= 4.7 && < 5+ , grakn+ , containers == 0.5.*+ , process == 1.4.*+ , aeson == 1.0.*+ , scientific == 0.3.*+ , text == 1.2.*+ , regex-posix == 0.95.*+ , servant == 0.9.*+ , servant-client+ , http-client+ , mtl+ , http-media+ , hspec+ , markdown-unlit+ , MissingH+ default-language: Haskell2010+ default-extensions: MultiParamTypeClasses+ , FlexibleInstances+ , FlexibleContexts+ , DataKinds+ , TypeOperators
+ src/Grakn.hs view
@@ -0,0 +1,48 @@+module Grakn+ ( MatchQuery+ , Graph(Graph, keyspace, url)+ , GraknError+ , Result(MatchResult, InsertResult, AskResult, CountResult,+ DeleteResult)+ , Var+ , Name+ , Value(..)+ , defaultUrl+ , defaultKeyspace+ , execute+ , match+ , select+ , distinct+ , limit+ , var+ , name+ , isa+ , (-:)+ , (.:)+ , rp+ , (<:)+ , rel+ , has+ , hasText+ , var_+ ) where++import Data.Text (Text)+import Grakn.Client (GraknError, Graph (Graph, keyspace, url), Result (AskResult, CountResult, DeleteResult, InsertResult, MatchResult),+ defaultKeyspace, defaultUrl, execute)+import Grakn.Pattern+import Grakn.Property+import Grakn.Query+import Grakn.Util (Convert)++-- |Specify a property has a particular type+(-:) :: (Convert p Pattern, Convert a VarOrName) => p -> a -> Pattern+(-:) = isa++-- |Shorthand to define a relation+rel :: Convert a RolePlayer => [a] -> Pattern+rel = (var_ <:)++-- |Specify a property has a resource+hasText :: (Convert p Pattern) => p -> Name -> Text -> Pattern+hasText = has
+ src/Grakn/Client.hs view
@@ -0,0 +1,115 @@+{-# LANGUAGE OverloadedStrings #-}++module Grakn.Client+ ( Graph(Graph, keyspace, url)+ , Concept(Concept, cid, cname, ctype, value)+ , GraknError+ , Result(MatchResult, InsertResult, AskResult, CountResult,+ DeleteResult)+ , defaultUrl+ , defaultKeyspace+ , execute+ ) where++import Control.Applicative (empty)+import Data.Aeson (FromJSON, ToJSON, encode, parseJSON,+ (.:), (.:?))+import qualified Data.Aeson as Aeson+import Data.Foldable (asum)+import Data.Map (Map)+import Data.Proxy (Proxy (Proxy))+import Data.Text (Text)+import Grakn.Property (Name, Value, Var)+import Grakn.Query (IsQuery (queryString))+import Network.HTTP.Client (defaultManagerSettings, newManager)+import Network.HTTP.Media ((//))+import Servant.API+import Servant.API.ContentTypes (eitherDecodeLenient)+import Servant.Client++data Graph = Graph+ { url :: BaseUrl+ , keyspace :: String+ }++newtype GraknError =+ GraknError String+ deriving (Eq, Show)++-- |A result of a match query, binding variables to concepts+data Result+ = MatchResult [Map Var Concept]+ | InsertResult [Text]+ | AskResult Bool+ | CountResult Integer+ | DeleteResult+ deriving (Show, Eq)++-- |A concept in the graph+data Concept = Concept+ { cid :: Text+ , cname :: Maybe Name+ , ctype :: Maybe Name+ , value :: Maybe Value+ } deriving (Show, Eq)++-- |The default Grakn URL, accessing localhost+defaultUrl :: BaseUrl+defaultUrl = BaseUrl Http "localhost" 4567 ""++-- |The default Grakn keyspace+defaultKeyspace :: String+defaultKeyspace = "grakn"++execute :: IsQuery q => Graph -> q -> IO (Either ServantError Result)+execute (Graph u ks) query = do+ manager <- newManager defaultManagerSettings+ let env = ClientEnv manager u+ runClientM (graqlGet (queryString query) ks) env++type Keyspace = QueryParam "keyspace" String++type Infer = QueryParam "infer" Bool++type Materialise = QueryParam "materialise" Bool++type Body = ReqBody '[ PlainText] String++type GraknParams+ = Keyspace :> Infer :> Materialise :> Body :> Post '[ GraqlJSON] Result++-- |A type describing the REST API we use to execute queries+type GraknAPI = "graph" :> "graql" :> "execute" :> GraknParams++graknAPI :: Proxy GraknAPI+graknAPI = Proxy++graqlGet :: String -> String -> ClientM Result+graqlGet query ks = client graknAPI (Just ks) (Just False) (Just False) query++instance FromJSON Concept where+ parseJSON (Aeson.Object obj) =+ Concept <$> (obj .: "id") <*> (obj .:? "name") <*> (obj .:? "isa") <*>+ (obj .:? "value")+ parseJSON _ = empty++instance FromJSON Result where+ parseJSON val =+ asum+ [ MatchResult <$> parseJSON val+ , InsertResult <$> parseJSON val+ , AskResult <$> parseJSON val+ , CountResult <$> parseJSON val+ , pure DeleteResult+ ]++data GraqlJSON++instance Accept GraqlJSON where+ contentType _ = "application" // "graql+json"++instance ToJSON a => MimeRender GraqlJSON a where+ mimeRender _ = encode++instance FromJSON a => MimeUnrender GraqlJSON a where+ mimeUnrender _ = eitherDecodeLenient
+ src/Grakn/Pattern.hs view
@@ -0,0 +1,58 @@+module Grakn.Pattern+ ( Pattern+ , var_+ , isa+ , (<:)+ , has+ ) where++import Grakn.Property+import Grakn.Util (Convert (convert), spaces, with)++-- |A pattern to find in the graph+data Pattern =+ Pattern (Maybe VarOrName)+ [Property]++-- |Create an anonymous variable+var_ :: Pattern+var_ = Pattern Nothing []++-- |Specify a property has a particular type+isa :: (Convert p Pattern, Convert a VarOrName) => p -> a -> Pattern+patt `isa` x = addProperty patt (Isa $ convert x)++-- |Specify a property is a relation between other variables+(<:) :: (Convert p Pattern, Convert a RolePlayer) => p -> [a] -> Pattern+patt <: cs = addProperty patt (Rel $ map convert cs)++-- |Specify a property has a resource+has ::+ (Convert p Pattern, Convert a (Either Value Var))+ => p+ -> Name+ -> a+ -> Pattern+has patt rt v = addProperty patt (Has rt $ convert v)++showProps :: Show a => [a] -> String+showProps = spaces . reverse++addPropToPattern :: Pattern -> Property -> Pattern+addPropToPattern (Pattern n props) prop = Pattern n (prop : props)++addProperty :: Convert a Pattern => a -> Property -> Pattern+addProperty = addPropToPattern . convert++instance Show Pattern where+ show (Pattern v []) = v `with` "" ++ ";"+ show (Pattern v props) = v `with` " " ++ showProps props ++ ";"++instance Convert Var Pattern where+ convert = convert . (convert :: Var -> VarOrName)++instance Convert Name Pattern where+ convert = convert . (convert :: Name -> VarOrName)++instance Convert VarOrName Pattern where+ convert v = Pattern (Just v) []
+ src/Grakn/Property.hs view
@@ -0,0 +1,145 @@+module Grakn.Property+ ( Property(..)+ , RolePlayer+ , Var+ , Name+ , VarOrName+ , Value(..)+ , var+ , name+ , (.:)+ , rp+ ) where++import Control.Applicative (empty)+import Data.Aeson (FromJSON, FromJSONKey,+ FromJSONKeyFunction (FromJSONKeyText),+ parseJSON)+import qualified Data.Aeson as Aeson+import Data.Scientific (Scientific)+import Data.Text (Text, unpack)+import Grakn.Util (Convert (convert), commas, with)+import Text.Regex.Posix ((=~))++-- |A property of a concept+data Property+ = Isa VarOrName+ | NameProperty Name+ | Rel [RolePlayer]+ | Has Name+ (Either Value Var)++-- |A variable name wildcard that will represent a concept in the results+newtype Var =+ Var Text+ deriving (Eq, Ord)++-- |A name of something in the graph+newtype Name =+ Name Text+ deriving (Eq)++-- |Something that may be a variable name or a type name+data VarOrName+ = VarName Var+ | TypeName Name++-- |A value of a resource+data Value+ = ValueString Text+ | ValueNumber Scientific+ | ValueBool Bool+ deriving (Eq)++-- |A casting, relating a role type and role player+data RolePlayer =+ RolePlayer (Maybe VarOrName)+ Var++-- |Create a variable+var :: Text -> Var+var = Var++-- |Create a name of something in the graph+name :: Text -> Name+name = Name++-- |A casting in a relation between a role type and a role player+(.:) :: Convert a VarOrName => a -> Var -> RolePlayer+rt .: player = RolePlayer (Just $ convert rt) player++-- |A casting in a relation without a role type+rp :: Var -> RolePlayer+rp = RolePlayer Nothing++nameRegex :: String+nameRegex = "^[a-zA-Z_][a-zA-Z0-9_-]*$"++instance Show Property where+ show (Isa varOrName) = "isa " ++ show varOrName+ show (NameProperty n) = "type-name " ++ show n+ show (Rel castings) = "(" ++ commas castings ++ ")"+ show (Has rt value) = "has " ++ show rt ++ " " ++ showEither value++instance Show RolePlayer where+ show (RolePlayer roletype player) = roletype `with` ": " ++ show player++instance Show Value where+ show (ValueString text) = show text+ show (ValueNumber num) = show num+ show (ValueBool bool) = show bool++instance Show Name where+ show (Name text)+ | str =~ nameRegex = str+ | otherwise = show text+ where+ str = unpack text++instance Show Var where+ show (Var v) = '$' : unpack v++instance Show VarOrName where+ show (VarName v) = show v+ show (TypeName t) = show t++instance Convert Var VarOrName where+ convert = VarName++instance Convert Name VarOrName where+ convert = TypeName++instance Convert Var RolePlayer where+ convert = rp++instance Convert Var (Either Value Var) where+ convert = Right++instance Convert Text (Either Value Var) where+ convert = Left . ValueString++instance Convert Scientific (Either Value Var) where+ convert = Left . ValueNumber++instance Convert Bool (Either Value Var) where+ convert = Left . ValueBool++instance FromJSON Value where+ parseJSON (Aeson.String s) = return $ ValueString s+ parseJSON (Aeson.Number n) = return $ ValueNumber n+ parseJSON (Aeson.Bool b) = return $ ValueBool b+ parseJSON _ = empty++instance FromJSON Name where+ parseJSON (Aeson.String s) = return $ name s+ parseJSON _ = empty++instance FromJSON Var where+ parseJSON (Aeson.String s) = return $ var s+ parseJSON _ = empty++instance FromJSONKey Var where+ fromJSONKey = FromJSONKeyText var++showEither :: (Show a, Show b) => Either a b -> String+showEither = either show show
+ src/Grakn/Query.hs view
@@ -0,0 +1,52 @@+module Grakn.Query+ ( IsQuery(queryString)+ , MatchQuery+ , match+ , select+ , limit+ , distinct+ ) where++import Grakn.Pattern+import Grakn.Property+import Grakn.Util++class IsQuery q where+ queryString :: q -> String++-- |A Graql 'match' query that finds a pattern in the graph+data MatchQuery+ = Match [Pattern]+ | Select MatchQuery+ [Var]+ | Limit MatchQuery+ Integer+ | Distinct MatchQuery++-- |Create a match query by providing a list of patterns+match :: Convert a Pattern => [a] -> MatchQuery+match = Match . map convert++-- |Select variables from a match query, intended to be used infix+select :: [Var] -> MatchQuery -> MatchQuery+select = flip Select++-- |Limit a match query, intended to be used infix+limit :: Integer -> MatchQuery -> MatchQuery+limit = flip Limit++-- |Retrieve only distinct results from a match query+distinct :: MatchQuery -> MatchQuery+distinct = Distinct++instance Show MatchQuery where+ show (Match patts) = "match " ++ spaces patts+ show (Select mq vars) = show mq ++ " select " ++ commas vars ++ ";"+ show (Limit mq lim) = show mq ++ " limit " ++ show lim ++ ";"+ show (Distinct mq) = show mq ++ " distinct;"++instance IsQuery MatchQuery where+ queryString = show++instance IsQuery String where+ queryString = id
+ src/Grakn/Util.hs view
@@ -0,0 +1,27 @@+module Grakn.Util+ ( Convert(convert)+ , with+ , commas+ , spaces+ ) where++import Data.List (intercalate)++class Convert a b where+ convert :: a -> b++instance Convert a a where+ convert = id++with :: Show a => Maybe a -> String -> String+(Just val) `with` suffix = show val ++ suffix+Nothing `with` _ = ""++commas :: Show a => [a] -> String+commas = interList ", "++spaces :: Show a => [a] -> String+spaces = interList " "++interList :: Show a => String -> [a] -> String+interList sep = intercalate sep . map show
+ test/Example.lhs view
@@ -0,0 +1,93 @@+# Grakn Haskell Client++A Haskell client for [Grakn](http://grakn.ai).++Requires Grakn 0.16.++# Installation++To install the Grakn client, simply add this to your cabal file:++```+build-depends: grakn+```++You will also need access to a Grakn database.+Head [here](https://grakn.ai/pages/documentation/get-started/setup-guide.html)+to get started with Grakn.++# Quickstart++Begin by importing the client:++```haskell+{-# LANGUAGE OverloadedStrings #-}++module Example where++import Grakn++import Data.Function ((&))+```++Define the type names:++```haskell+person :: Name+person = name "person"++husband :: Name+husband = name "husband"++wife :: Name+wife = name "wife"++marriage :: Name+marriage = name "marriage"+```++Define the variables:++```haskell+x :: Var+x = var "x"++y :: Var+y = var "y"+```++We can translate the following query into Haskell:++```graql+match $x isa person, (husband: $x, wife: $y) isa marriage; select $y;+```++```haskell+query :: MatchQuery+query = match+ [ x `isa` person+ , rel [husband .: x, wife .: y] `isa` marriage+ ] & select [y]+```++We can also use infix functions like `(-:)` instead of `isa`:++```haskell+otherQuery :: MatchQuery+otherQuery = match+ [ x -: person+ , rel [husband .: x, wife .: y] -: marriage+ ] & select [y]+```++To execute and print the results of our query:++```haskell+graph :: Graph+graph = Graph defaultUrl "my-keyspace"++main :: IO ()+main = do+ result <- execute graph query+ print result+```
+ test/Main.hs view
@@ -0,0 +1,1 @@+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}